Winter Maintenance & Operations Flashcards

What is the primary purpose of anti-icing in winter road maintenance?

Answer: Apply chemicals before a storm to prevent bond formation

Anti-icing applies liquid chemicals before precipitation to prevent ice from bonding to the pavement surface.

At what pavement surface temperature does rock salt (NaCl) lose significant effectiveness?

Answer: 15°F (-9°C)

Rock salt becomes significantly less effective below approximately 15°F (-9°C) and should be supplemented or replaced with other products.

Which de-icing chemical is most appropriate when pavement temperatures drop below 15°F (-9°C)?

Answer: Calcium chloride (CaCl2)

Calcium chloride generates heat as it dissolves and remains effective down to approximately -25°F (-32°C), making it suitable for very cold conditions.

What is the recommended maximum application rate for liquid anti-icing materials on Kansas highways in most conditions?

Answer: 20-30 gallons per lane mile

KDOT guidelines generally recommend 20-30 gallons per lane mile for liquid anti-icing applications to balance effectiveness and cost.

During a winter storm, what does 'Level of Service B' typically mean for KDOT operations?

Answer: Bare pavement within 4 hours of storm end

Level of Service B targets bare pavement conditions within 4 hours after a storm ends on designated route classifications.

Which piece of equipment is used to apply liquid de-icing materials directly to the road surface?

Answer: Plow with direct liquid application (DLA) system

Direct Liquid Application (DLA) systems spray liquid chemicals directly onto the pavement without requiring solid material.

What is 'prewetting' in the context of winter maintenance?

Answer: Adding liquid to dry granular de-icing material at the spinner

Prewetting involves adding liquid chemical to dry granular material at the point of application to help it adhere to the road and activate faster.